Samuel b



(No Model.)

S. B. WHITEHEAD.

TBLEGRAPHIC APPARATUS.

A Patented Jan. 17, 18881.;

Am: enfem @WvA mum,

SAMUEL l3. WHITEHEAD, OF SAN FRANCISCO, CALIFORNIA.

TELEGRAPl-HC APPARATUS.

srncrrrcarron forming part of Letters Patent No. 376,569, dated January iv, was.

Application filed August 9, 1887.

trol the sound of transmitting and receiving instruments; second, to so arrange the transmuting and receiving instruments as to prevent unscrupulous persons with a knowledge.

of telegraphy from stealing messages by means eavesdropping; third, to do away with the noise and disturbance caused by the simultaneous working of many instruments in one room; fourth, to providea means whereby the manager or other privileged person may hear the tickingof any particularinstrument; fifth, to so arrange the apparatus that while accomplishing the foregoing objects it shall not in any way obstruct the operator in the performance of his duty of receiving, transmitting, and

transcribing messages; sixth, to so devise the apparatus that should the operator have occasion to leave his instrumentit can be arranged to attract the attentionof himself or others when the sounder commences to operate. I accomplish these objects by means of the devices illustrated in theaccompany'ing draw- 7 described, incloses thetelegraphic instrument,

ings, in which- Figurel isaview of my device inoperation, portion being sectioned. Fig. 2 is a viewof head-clamps and ear-pieces. Figs. 3 andA are modifications of f and f Fig. 5, detail of cover-packing.

A is a box containing telegraphic instrument. a is a cover or lid; a, non-conducting material; B, acoustic tube; G, sound-gatherer; D, flexible acoustictube; E, transmitting-key;

F F, packing; f ',transmitter-key and switch rods, respectively; G, ear-pieces; H, headclamps; I, Y-branch connection; J, an elastic cord or spring; f, a washer; f spring; f, collar; f flexible washer; N, packing for lid.

The construction and operation of the device are as follows: The box A, which incloses Serial No. 246154 (No model:)-

a telegraphic transmitting and receiving instrument, is made of suitable soundnon-con ducting material, or otherwise made to be as perfecta sound non-conductor as possible. The manner shown in the drawings, Fig. 1, I con.- sider preferable, the construction of which is as follows: The sides, top, and bottom are made double, a sufficient space being left between the double plates, which is filled with any sound non-conductor. Holes are'provided at suitable places in the sides of the box for rods to pass through .to operate the transmitter and switch. These holes are suitably packed to prevent the escape of sound. This may be accomplished in various ways, three of which I show-one at f f, Fig. 1, in which the rods are surrounded by and worked through-a packing of fibrous orelastic nature. Other forms, which are shown in Figs. 3 and 4, will be more fully explained hereinafter.

.The box which incloses the telegraphing-instrument is provided with one or more acoustic tubes of suitable size and material, which pass into the interior for the purpose of conveying the sound of the instrument to the out side of the box. These tubes may be-extended to any desired length or' position, or may be attached to flexible tubes for convenience of use, these flexible tubes to be supplied with suitable ear-pieces.

The arrangement illustrated in Fig. 1 shows the manner in which I preferably construct the apparatus and from which I have derived the best results. The double-walled box A, as

to retain the ear-pieces in position, thereby obviating the-necessity of his holding them in position. The cord J suspends the headclamps and ear-pieces in a convenient position, and is of elastic material, and thus allows of considerable movement of the operator without inconvenience. The other acoustic tube, which is not intended for constant use, is provided with a single ear-piece.

A portion of the box A over the sounder is hinged,so that it can be raised, that when this cover is open the sounder can be heard like any ordinary instrument, so that if the operator desires to leave his instrument the attention of himself or others may be drawn to it should the sounder commence to operate. The edges of this cover or lid, and also that portion of the box upon which it rests when closed,is provided with felt or other suitable material, to prevent sound from issuing from between the joints of the cover and box. This is shown at N in Fig. 1 and also in detail in Fig, 5.

In Figs. 3 and 4 I show two ways of preventing the egress of sound from the holes through which the transmitter-key and switch are worked. Around the edge of the earpiece where it comes in contact with the head of the operator it is provided with a pad of soft material-such as wool or chamois-skinto prevent constant use from inconveniencing the wearer, and also to make as close a joint as practicable between the head and ear pieces, and so prevent the escape of sound In Fig. 3 the washers f are secured to the rod E in such position as to keep the spring slightly compressed against the washers when the rod E is in its normal position. The washers f 2 are of felt, or other material of a yielding or elastic nature, and fit somewhat tightly around the rod E.

In Fig. 4 the washers f 5 are of a flexible and elastic material, and are secured iulposition by pins near their periphery.

avessa Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. Ina muffled telegraphic message receiving and transmitting instrument, a box all the sides of which are made with an inner and outer casing, and the space between the easings filled with suitable non-conducting mate- 5 tained, the tubes BB, sound-collector G, stems E and E, for operating the transmitting instruments from the outside of the box, flexible pipe D, witlrits branches H H, ear-pieces G, having their edges padded and conforming to the contour of the human head around the ear, the head-clamp H, and elastic sustaining-cord J, all arranged and operating substantiallyas described.

SAMUEL B. \VHITE HEAD.

Witnesses:

GEo. W. WEFFIINGER, H. H. KIRK. 

